Structural and photoluminescent characteristics of porous GaAs capped with GaAs

In this paper, we present the results of structural and room temperature photoluminescence studies on porous GaAs (pi-GaAs) capped with GaAs. The porous structure formation was confirmed by scanning electron microscopy (SEM) and relatively homogeneous pores of diameters as small as 4 nm was grown along < 111 > B directions. X-ray diffraction (XRD) investigations confirm the high crystal quality of the capping layer and a lattice mismatch of 4% between the two layers was determined. The room temperature photoluminescence (PL) spectrum of porous GaAs recorded during steady-state excitation shows a strong PL covering the red-blue band. Time resolved photoluminescence (PLAT) investigations provide evidence for the existence of PL components with different origins.